Vaccines are one of the most effective preventative health tools available against infectious diseases, cancers, and allergies. Vaccination aims to generate a strong immune response to the administrated antigen and provide long-term protection against a disorder. Often, however, an antigen alone is insufficient to stimulate protective immunity.
Vaccine adjuvants are compounds that enhance the specific immune responses against antigens in vaccines. Currently, several hundred natural and synthetic compounds are known to have adjuvant activity but only alum salts and AS04 are licensed for use in humans in the United States. This limited list of adjuvants is insufficient for meeting the functional needs of effective vaccination. For example, although alum is able to induce a good TH2 response, it has little capacity to stimulate cellular (TH1) immune responses which are so important for protection against many pathogens.
Accordingly, there remains a need for improved vaccines and/or adjuvants that can effectively stimulate a subject's immune response.